Oleg first fought MMA before the UFC ever existed. He fought in the White Dragon tournament in Riga,Latvia in 1993. He beat 3 fighters that night. The UFC called this event the European Iron Gladiator Tournament.

One of the staple fighters of the UFC's one-night tournaments of the 1990s, Russian fighter Oleg Taktarov was the winner of the UFC 6 tournament and holds career victories over Tank Abbott, Marco Ruas, and Mark Kerr. A Sambo specialist, Taktarov was known for his exceptional grappling ability and the calm he demonstrated in the face of adversity during his fights. Although he was finished several times, including by a memorable knockout upkick by Renzo Gracie, Taktarov was never submitted during his career, and he won the vast majority of his fights by submission.

Taktarov suffered a loss at UFC when he lost in the semi-finals to Dan Severn from a stoppage due to a cut. The fight was stopped because of profuse bleeding, but Taktarov insists that he could have continued and to this day does not consider the loss an actual loss. Between UFC 5 and 6, Taktarov lived and trained with Ken Shamrock's Lion's Den team. 

In addition to his MMA career, Taktarov is a successful Hollywood film actor, having appeared in JAG, Air Force One, Bad Boys II, Alias, National Treasure, We Own the Night, and the 2010 remake of Predators, among other pictures.

Oleg has always been known for his toughness.  At the age of 19, he had sever appendicitis while in the Soviet armed forces but was on guard duty so he had to wait due to fear that he would be punished for not being able to do his job.